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Adcom 555se on a smart strip?

I'm thinking about a used Adcom 555se to power my new Ohm Walsh 4000s as recommended by John and Evan. This amp doesn't have a 12v trigger. My stereo "area" is the living room and the preamp will sit in the built-in cabinets next to the fireplace. I don't really want to put a high powered amp in the cabinet for ventilation reasons, so the basement seems like a good choice (and save space in the cabinets for more LPs). With no 12v trigger to power the amp on/off, I was thinking about having the preamp plugged into the control outlet of a smart power strip, and the amp plugged into one of the switched outlets. This will of course work for powering on, but I'm concerned about powering off. When powering off the preamp which will happen first, will it create a pop sound before the amp gets shut off? 

If this smart strip is a viable way to go in this situation, the used 555se will be a great cost savings. If not, I'll start looking at the Adcom 575se or maybe the Parasound A21+. 

Thanks guys and gals.
keysrawk
keysrawk OP
15 posts
 
I guess coming from the pro audio world and being a bit of a n00b with the hi-fi stuff, I'm confused as to how a 12v trigger powers off an amp appropriately. Maybe this doesn't matter as much in hi-fi. I always shut off amps first, then any other equipment. Perhaps the preamp and amp shut off exactly at the same time?

How could a Parasound P6 output trigger turn off the amp first before the P6 itself goes off? Or, for amps that have auto-sensing audio triggers (not 12 volt), they usually remain on for 5 minutes after no signal, then shut off. Does that mean I tell my wife and kids to wait 5 minutes after their done listening to music before shutting off the preamp? You know that isn't going to work.
stereo5's avatar
stereo5
6,266 posts
 
One thing I don’t understand is everyone’s love for Adcom.  I had an entire Adcom system with Vandersteen 2Ci speakers and never warmed up to it.  I found the Adcom 555 II to be a bit bright and hard sounding and moved on after a couple of years.  I had their top preamp which I also didn’t have much regard for.  I did like the FM tuner and their CD player and kept it until I bought the Pioneer Elite PD65  CD player.  
Am I the only one who feels this way about Adcom?  I will say after I traded the Adcom amp and pre and went to Classe’ electronics, the Vandersteen speakers really opened up and I enjoyed that system for the next 5 years without changing anything. 
keysrawk OP
15 posts
 
The topic is 12 volt triggers and power off sequences. Thanks.
gdnrbob
4,411 posts
 
@OP,
First, you turn on the system Preamp first then amp. Reverse when turning off. That way you don't get the turn on 'bump'.
As far as power strips go, I don't recommend them for high power demanding equipment like amplifiers.
I owned the original 555 amp and it never got 'that' hot, but if your cabinet has no ventilation then, maybe, put it on top or on the floor?
Bob
rhljazz
1,250 posts
 
I looked up the specs for the Adcom 555se and it is specified at consuming 72w at idle.  So depending on frugality, you could leave it powered on continuously.
By comparison, my W4S ST500 consumes 28w at idle.  I leave it powered on all the time.  The preamp in that system is a Manley Shrimp and I never receive any noise when the preamp is switched on or off.
So, that’s an option to consider.
Doing the math for 72w continuous for a month yields roughly 52kwh consumed. Electric rates vary, but let’s use 22 cents per kWh which would cost you $11.44 per month whereas an ST500 would run $4.44 per month.  These figures are idle consumption only.  The more you play, the more you pay.
Class D is more efficient while playing as well.  
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